Tap Water Quality Report
Tap water quality in PETALUMA, California
Tap water in PETALUMA, California receives a grade of D (68/100) from TapWaterSafety.org. It's served by PETALUMA, CITY OF. The most significant water quality concerns are: Arsenic significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in PETALUMA's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving PETALUMA.
Arsenic significantly above health guideline
Moderate concernArsenic detected at 3.0 ppb, 750x above the EWG health guideline of 0.004 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 36.2 ppb, 362x above the EWG health guideline of 0.1 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 25.4 ppb, 170x above the EWG health guideline of 0.15 ppb.
EPA compliance record
Official U.S. EPA records for PETALUMA, CITY OF (system ID CA4910006) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for PETALUMA
Filters matched to the specific contaminants in PETALUMA's water supply.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in PETALUMA's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Arsenic Heavy metal |
3.0 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 750× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
25.4 ppb | 0.15 | 80.0 | 100 | — | — | — | 170× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
9.47 ppb | 0.06 | — | — | — | — | — | 158× over |
| Bromodichloromethane Disinfection byproduct |
7.5 ppb | 0.06 | — | — | — | — | — | 125× over |
| Dibromochloromethane Disinfection byproduct |
5.02 ppb | 0.1 | — | — | — | — | — | 50× over |
| Trichloroacetic acid Disinfection byproduct |
4.1 ppb | 0.1 | — | — | — | — | — | 41× over |
| Dichloroacetic acid Disinfection byproduct |
6.61 ppb | 0.2 | — | — | — | — | — | 33× over |
| Chloroform Disinfection byproduct |
12.5 ppb | 0.4 | — | — | — | — | — | 31× over |
| Dibromoacetic acid Disinfection byproduct |
0.875 ppb | 0.03 | — | — | — | — | — | 29× over |
| Chromium (hexavalent) Heavy metal |
0.338 ppb | 0.02 | — | — | — | — | — | 17× over |
| Nitrate Inorganic |
0.289 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.1× over |
| Bromoform Disinfection byproduct |
0.4 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
54.4 ppb | 100.0 | — | 50 | 80 | — | — | Fails EU |
| Vanadium Other |
2.39 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
58.0 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Molybdenum Other |
1.07 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Dichloromethane (methylene chloride) Volatile organic compound |
0.0646 ppb | 4.0 | 5.0 | — | — | — | — | Below guideline |
| Aluminum Heavy metal |
5.3 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| Chlorate Disinfection byproduct |
1.13 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.29 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.106 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Germanium Other |
0.0321 ppb | — | — | — | — | — | — | Below guideline |
| o-toluidine Other |
0.01 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from PETALUMA, CITY OF.